\documentclass{article}
\usepackage[landscape]{geometry}% http://ctan.org/pkg/geometry
\usepackage{array}% http://ctan.org/pkg/array
\begin{document}

% =========== FACTOR approach ===========
{\renewcommand{\arraystretch}{2}%
\begin{tabular}{|l|l|}
  \hline
  column 1 & column 2 \      \hline
  I really would like this less & crammed \      \hline
\end{tabular}} \quad
% =========== LENGTH approaches ===========
\begin{tabular}{|l|l|}
  \hline
  column 1 & column 2 \\[4ex]
  \hline
  I really would like this less & crammed \\[5pt]
  \hline
\end{tabular} \quad
{\setlength{\extrarowheight}{20pt}%
\begin{tabular}{|l|l|}
  \hline
  column 1 & column 2 \      \hline
  I really would like this less & crammed \      \hline
\end{tabular}}
\end{document}
